[yolesaber]

The idea of names as power comes from pre-unified Ancient Egypt in which (i may have gotten the kingdoms mixed) the upper kingdom's religious rituals included the use of secret and ceremonial names known to only an elite literate cabal. From there the religion developed to include aspects of secret names for anything and everything and religious texts indicated that people believed once they learned something's secret name they would be able to exert control over them.

In fact, most of the concepts one associates with 'magic' (sigils, astronomical connotations, power words) derive from the Ancient Egyptian religion. See Wallace Budge's "Egyptian Magic" for an excellent treatment on the subject. His book has tons of direct primary source examples that are very entertaining (people turning into crocodiles, priests trying to shape the outcome of wars by creating effigies, lots of fun stuff)